I'm not entirely sure what you just said but fat has the same amount of fat whether it's in the form of butter, margarine, or oils, the fact that margarines can state that they have less fat comes in the form of what they are mixed with i.e., all the surrounding crap, since fat, gram for gram equates to the same calorie value...meaning that anything which states "lower fat" in relation to another fat, has to contain lots of nothings added to the fat spread...if you follow that.

Have a chunk of butter = 100% fat

Place the same chunk of butter in the equivalent amount of water = 50% fat